Lion Heart Imitate

Maybe. I got it up to 148 but still there is a couple dwarven hammers in there as well.

There's a few weapons notorious for being nearly impossible to max without the cash enhancement, this is one of them

Its between accuracy and overall damage. There won't be a right answer. You need accuracy to even land hit on evade build and several evade unit, but without that build assault should be worth it if you had nothing else since it affect your overall damage IMO.

what is the +5 bonus effect for this?

nah, don’t worry. It’s up there

A XIV event had yet to repeat in JP but it should come back again eventually.

Why would it though? It's just a meaningless event with less than spectacular rewards and an UR unit that's way too expensive for what it's worth.